1. Field of the Invention
The present invention relates to a device for changing the resolution of a facsimile. More specifically, the present invention relates to a device for changing the resolution of a facsimile that converts the resolution, without a separate electrical control.
2. Description of the Related Art
A transmission process of a contemporary facsimile requires a resolution of the facsimile. In order to change its resolution, a reference resolution is mechanically realized, and then the final resolution is electrically realized. The amount of information needed is obtained from data having the original resolution, and a predetermined amount of the information is electrically added or subtracted, to thereby create a resolution different from the original. One method of electrically changing the resolution of a facsimile is disclosed in Korean Pat. No. 92-2852. This method can be summarized as follows. In case of an even mask (the mask being even) in the vertical direction, the first row of third row and third column is changed into the brightness of the first picture element, the intermediate brightness between the first and second picture elements, and the brightness of the second picture element. If the mask is also even in the horizontal direction, and the first and second picture elements are black, the second row is changed into a pattern of white, black, and white. When the mask is odd in the horizontal direction, and the first and second picture elements are black, the second row is changed into black, white, and black. When one of the first and second picture elements is not black, the second row is changed into the brightness of the first picture element, the intermediate brightness between the first and second picture elements, and the brightness of the second picture element. In such a circumstance, the third row is changed into the brightness of the third picture element, the intermediate brightness between the third and fourth picture elements, and the brightness of the fourth picture element.
Where there is an odd mask (the mask not being even) in the vertical direction, the first row of third row and third column is changed into the brightness of the first picture element, intermediate brightness between the first and second picture elements, and brightness of the second picture element. When the mask is odd in the horizontal direction, and the third and fourth picture elements are black, the second row is changed into black, white, and black. When the mask is odd in the horizontal direction, and the third and fourth picture elements are black, the second row is changed into white, black, and white. When one of the third and fourth picture elements is not black, the second row is changed into the brightness of the first picture element, intermediate brightness between the first and second picture elements, and brightness of the second picture element, and the third row is changed into the brightness of the third picture element, intermediate brightness between the third and fourth picture elements, and brightness of the fourth picture element. By doing so, the resolution is increased. Thus, the picture quality is improved.
In the method discussed in the previous paragraphs, the original data is electrically processed to form data having the needed resolution. Accordingly, the process is complicated; it is difficult to perform. Furthermore, since the electrical process requires a predetermined time and separate hardware, the facsimile cost is increased. Moreover, the resolution realized through the electrical process is poorer; it is impossible to obtain a high-resolution image.
On these matters of resolution, facsimiles, and gears, among exemplars of the contemporary art and practice, Goldschmidt et al. (U.S. Pat. No. 5,626,585, Arrangement For High-Resolution Scanning Of Large Image Formats With Exact Geometrical Correspondence, May 6, 1997) discusses a scanning resolution improved by using a special pixel raster method. Ko (U.S. Pat. No. 5,369,509, Document Transferring System For A Facsimile Apparatus, Nov. 29, 1996) discusses a document transferring system including at least two drive gears and an idler gear. Miura (U.S. Pat. No. 5,062,006, Sheet Feeding Apparatus And Facsimile System Having Same, Oct. 29, 1991) discusses control of a stepping motor interacting with a discrimination means. Vano (U.S. Pat. No. 4,262,310, Facsimile Recorder Framing Circuit, Apr. 14, 1981) discusses transmitting power to the recorder motor at a particular frequency. Takeuchi (U.S. Pat. No. 5,239,393, Image Reading Apparatus, Aug. 24, 1993) discusses a reading device for reading an image line by line. Upon reception of the image reading resumption signal generated from the computer, the driving force initiates supply of the driving signal to the moving device. Crane et al. (U.S. Pat. No. 3,699,249, Facsimile Systems, Transceivers, And Marking Transducers Therefor, Oct. 17, 1972) discusses a transceiver including rotary members which rotate past an arcuately disposed document to transmit the information on the document or to receive and record facsimile information on the document. The transceiver has a transducer. From my study of the contemporary practice and art, I find that there is a need for an improved and effective device for changing the resolution of a facsimile that converts the resolution, without a separate electrical control, using gears only and changing the rotation direction of a driving motor of the facsimile machine.